Defini??o de idades ótimas para expedi??o de mudas de Araucaria angustifolia (Bertol.) Kuntze (Araucariaceae) em fun??o de sua qualidade e volume de recipientes

摘要

The objective of this study was to evaluate the quality and development of Araucaria angustifolia (Bertol.) Kuntze seedlings, considering different ages and their growth in different size tube, aiming to determine the optimal age for transfer of nursery seedlings. Three volumes of tubes (50, 100 and 200 cm3) were used and four transfer ages (90, 120, 150 and 180 days) were tested. The study was conducted using a completely randomized design with 3 x 2, factorial arrangement of treatments, five replications per treatment and a total of 2,400 plants. The evaluations were performed monthly, using five seedlings of each repetition and randomly selected. The following variables were determined on each occasion: height, stem diameter, root dry mass, aerial dry mass, number of secondary roots and Dickson quality index. Only the variables height, aerial dry mass and number of secondary roots showed significant differences between treatments. The ages found to be optimal for the transfer of the araucaria seedlings were 120 days when in a 50-cm3 tubes and 150 days when in 100-cm3 tubes. For seedling maintenance in nurseries for periods longer than 150 days, the use of 200-cm3 tubes was found more appropriate.